Litecoin's trade volume dwarfs most other coins.
Litecoin is supported by a huge number of exchanges. No other altcoin comes close.
Like the comparison or not, Litecoin is silver to Bitcoin's gold. Having a cryptocurrency trading pair is important for arbitrage reasons. Litecoin is playing that role today. It's hard for another coin to take over that role.
spot on about LTC! I like #3, how BTC is todays gold and LTC is todays silver